Patent Documents 1-3 below set forth a spout apparatus utilizing an oscillating phenomenon based on a fluid device. In such spout apparatuses, the spout water spray direction can be changed without providing a movable member, thus affording the advantage that a spout apparatus capable of spouting over a wide range can be achieved using a simple and compact constitution.
In the spout apparatus set forth in Patent Document 3 below, as shown in FIG. 13, a fluid which has flowed into an antechamber 110 from an intake hole 114 first collides with an obstacle 116 having a triangular cross section, and disposed as an island within the antechamber 110. When the fluid collides, Karman vortices are alternately formed on the upper and lower sides of the obstacle 116, resulting in a vortex street. This Karman vortex street reaches the outlet 112 as it grows. Close to the outlet 112, the flow velocity on the side where the vortex street is present speeds up, and the flow velocity on the opposite side thereto slows down. In the example shown in FIG. 13, the Karman vortices occur alternately on the upper and lower sides of the obstacle 116; these vortex streets sequentially reach the outlet 112, thereby alternately producing a high flow velocity on the upper side and a high flow velocity on the lower side. In the high flow velocity state on the upper side, the high velocity fluid collides with a wall surface 110a on the upper side of the outlet 112 and is changed, while the fluid sprayed from the outlet 112 forms a spray flow which in total is directed diagonally downward. In the high flow velocity state on the lower side, on the other hand, the high flow velocity fluid collides with a wall surface 110b on the lower side of the outlet 112, and a spray flow is sprayed diagonally upward from the outlet 112. Alternating repetition of such states results in the spray flow from the outlet 112 being sprayed as it oscillates in a reciprocating manner. Using a spout apparatus of this type, a spout apparatus can be achieved which is capable of spraying over a broad range while being extremely simple and compact.